Brettanomyces is used in a wide range of beers to produce its signature funky and fruity aromas. The funk mostly comes from volatile phenol compounds, like 4-ethylguaiacol (wood smoke, bacon) and 4-ethylphenol (band-aid, barnyard). The fruitiness comes from esters, especially the "fatty acid esters" ethyl caproate, ethyl caprylate, and ethy decanoate, which offer up a host of pineapple and orchard fruit aromas.
I haven't messed with Brett at all. It also is something I'm not sure would be a good choice for spirits. I would like to try it sometime but that may be far into the future.This is the critical challenge of Brett primary fermentation: it's slow. Even with an ideal strain under ideal conditions, the fermentations took at least three weeks.